How to avoid log10 from calculating for log values or if its calculated for complex log how do i avoid it?

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Ganesh on 10 Nov 2023
Edited: Stephen23 on 10 Nov 2023
for example if code
log10(-3) i get
ans =
0.4771 + 1.3644i
but as we know log isn't defined for negative value. My objective is to calculate the correction factor for acoustic measurement the code is as follows and the how do i avoid this function calculating the log value of negative numbers.
% when delta is in the range of [-4,4];
delta=-10:0.1:10
K_factor=-(10*log10(1-10.^(-0.1*delta)))
%SPls=10*log10(10^(SPLt/10) - 10.^(K_factor./10))
plot(delta,K_factor)
xlabel("Delta Value");
ylabel("K Factor")

Stephen23 on 10 Nov 2023
Edited: Stephen23 on 10 Nov 2023
"how do i avoid this function calculating the log value of negative numbers."
Don't call the function with negative values.
delta = -10:0.1:10;
V = 1-10.^(-0.1*delta);
X = V>0;
K_factor = nan(size(delta));
K_factor(X) = -10*log10(V(X));
plot(delta,K_factor)